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The mechanism of emplacement for Mississippi Valley type (MVT) lead- zinc deposits of southeast Missouri (viburnum trend) has been much debated. One relatively new school of thought is that the lead-zinc mineralization in the viburnum trend may have occurred during late Pennsylvanian time in association with uplift of the Ouachita Mountains. A plumbing system through the lamotte sandstone with an appropriate hydraulic gradient associated with uplift of the ouachitas is thought to have made it possible for ore fluids to be driven from deep basins to their present site. Fluid inclusion studies on dolomite suggest that the whole sequence of lower Paleozoic carbonates in Missouri appears to have been exposed to slightly anomalously high temperature (77 to 110 deg c) upward moving hydrothermal fluids. This research project is examining the "stewed" hypothesis by looking at vitrinite reflectance and thermal maturation of coals in sinkholes of the East-Central Fireclay District to determine the extent to which these coals have been exposed to anomalous temperatures. Vitrinite is one of the most common coal macerals, and it occurs in small amounts in most post- Devonian clastic sedimentary rocks. When vitrinite is exposed to increasing temperature it releases methane while simultaneously incorporating fixed carbon into napthenic ring structures.